Enhancing the light absorptance of stain-etched black silicon decorated by TiN nanoparticles

Abstract

Due to the high energy, narrow distribution and breaking through the absorption limitation, plasmon induced hot electrons has been widely applied to extend the photoresponse spectra of the semiconductor. In order to further enhance the resonance effect of local plasmon based on metallic nanostructures, we used hydro uoric stain etching method to fabricate nanostructured black silicon (BSi) and deposited titanium nitride (TiN) nanoparticles on its surface by reactive magnetron-sputtering. The results show that the BSi modi ed by plasmonic TiN nanoparticles has higher absorption in wavelength range from 1100 to 2500 nm compared to that of conventional acid etching of BSi. A PIN photoelectronic detector fabricated by the proposed BSi shows excellent device performance with responsivity of 0.45A/W at 1060 nm in near infrared band.

Tailoring Femtosecond‐Laser Processed Black Silicon for Reduced Carrier Recombination Combined with >95% Above‐Bandgap Absorption

“…[1][2][3][4] It is generally acknowledged that the antireflection effect due to the surface textures contributes to the high absorptance for wavelengths below 1.1 μm, [5] which applies especially to the visible range (400-750 nm) and as a result the bSi shows darkened color to naked eyes. High visible absorption can be obtained with different fabrication methods with optimized surface morphology, and those methods include, e.g., electrochemical etching, [6] stain etching, [7] metal-assisted chemical etching, [8] reactive ion etching, [9] and so on. Among these methods, the high-intensity femtosecond-pulsed laser is a promising alternative to process black silicon surface (fs-bSi).…”

Mg$_2$Si is the new black: introducing a black silicide with $>$95% average absorption at 200-1800 nm wavelengths

“…However, the former material clearly demonstrates slightly increased VIS reflection with specific silicide related spectral feature at 500 nm (2.5 eV) resulted from first direct interband optical transition in Mg 2 Si 32 . This fact suggests that Mg 2 Si nanoflakes provide enough area for the sur- 2a) and compared to state-of-the-art black surface structures 13,14,16,20,[33][34][35] (Figure 2c). Optical absorption spectra (A) calculated as 1-T-R demonstrate that optical properties of the b-Si changed drastically after Mg 2 Si deposition.…”

“…Next, FDTD calculations were performed to study the effect of b-Si covering with Mg 2 Si layer. Figure 2b E /E 0 @1300 nm E 1200 1800 2400 [17] This work [16] [35]…”

“…[34] 13,14,16,20,[33][34][35] Significantly, the wide range optical absorption performance of the black silicide is compared with state-of-theart approaches to enhance NIR efficiency of the b-Si as shown in Fig. 2c.…”

“…Thus, it is expected that near-infrared (NIR) absorbing layer deposited above b-Si surface would result in extension of its spectral blackness. So far, b-Si structures have been modified via thin film or nanoparticles deposition, formation of the hierarchical carbon-based nanostructures atop or pulsed laser postprocessing [13][14][15][16][17][18][19][20][21] . To date, practical use of the outlined approaches is limited by the low cost-efficiency factor resulted from the expensive deposition methods applied (atomic-layer deposition, molecular-beam epitaxy, etc. )…”